ISIS , as the Islamic State jihadists in Iraq and Syria are known , has become the new face of international terrorism in the eyes of the United States and its Western allies .

Now the focus in America and abroad has become what will President Barack Obama and other leaders do about it ?

Here are key questions on the matter :

1 -RRB- Who killed James Foley ?

Britain 's ambassador to the United States , Peter Westmacott , told CNN on Sunday that British officials were close to identifying the ISIS militant who beheaded Foley , an American journalist captured in Syria in 2012 .

He could n't elaborate on the identity of the killer , who is seen decapitating Foley in a video posted last week on YouTube .

`` We 're putting a great deal into the search , '' he said , referring to the use of sophisticated technology to analyze the man 's voice .

In the video , Foley , 40 , is seen kneeling next to a man dressed in black , who speaks with what experts say is a distinctly English accent .

Linguists said that based on his voice , the man sounds to be younger than 30 . He also appears to have been educated in England from a young age and to be from southern England or London .

Britain close to identifying James Foley 's killer , ambassador says

2 -RRB- Will the United States expand air strikes to ISIS targets in Syria ?

Pressure is increasing on Obama to go after ISIS in both Iraq and Syria , ignoring an essentially non-existent border between them .

Last week , Defense Secretary Chuck Hagel and Joint Chiefs Chairman Gen. Martin Dempsey said that taking on ISIS in Syria was the only way to defeat the Sunni jihadists .

For Obama , the step would reverse his refusal for three years to get involved militarily in Syria despite pressure from his own advisers , including former Secretary of State Hillary Clinton .

Obama `` has not made any decision to order military action in Syria , '' White House spokesman Josh Earnest said Monday , but the speculation and insistence continued .

`` The White House is trying to minimize the threat we face in order to justify not changing a failed strategy , '' conservative GOP Sen. Lindsey Graham of South Carolina said Monday .

CNN National Security Analyst Peter Bergen said it will be difficult to defeat ISIS without ground forces , something Obama clearly opposes . Intervening in Syria also could result in some strange geopolitical bedfellows , he noted .

`` Two of the most effective fighting forces in Syria are al Qaeda or al Qaeda splinter groups , or groups like Hezbollah , backed by Iran , '' Bergen said . `` So if you intervene , you may be helping Iran and Hezbollah and -LRB- Syrian President Bashar al-Assad 's -RRB- regime . ''

Obama already sent military advisers to Iraq and launched air strikes to protect them and minority groups from ISIS fighters rampaging through the country 's north .

Is Obama heading toward airstrikes in Syria ?

A White House spokesman said last week that Obama would consult with Congress before taking such a step in Syria . The President also would seek to forge a coalition including regional allies as well as U.N. and European Union support , officials have made clear .

Republicans urge airstrikes in Syria to defeat ISIS

3 -RRB- Will the Syrian regime that Obama opposes help fight ISIS ?

Obama wants al-Assad out of power , but now the Syrian leader engaged in a civil war against a U.S.-backed opposition is offering to help him take on ISIS .

Foreign Minister Walid Moallem said Monday his government would accept support from the United States and others working under the U.N. umbrella to fight `` terrorists '' -- a code word for the group that calls itself the Islamic State and seeks to establish a caliphate across a Sunni-dominated swath of the the Middle East .

Moallem , however , warned against any unilateral action or strikes in Syrian territory without its permission , saying `` any effort to fight terrorism should be done in coordination '' with the `` Syrian government . ''

Last week , Atlantic Council senior fellow and Syria expert Frederic Hof said a U.S. rescue mission for Foley earlier this year that went into Syria but failed to find him established the precedent for military action across the Iraq border , superseding any legal considerations such as being asked by the host government to enter .

`` The sort of legal barrier that prohibited doing something inside Syria now seems to have evaporated , '' Hof said .

The Syrian offer to help fight ISIS comes after al-Assad 's government enabled the group to expand amid the Syrian civil war . ISIS fighters have attacked the Syrian opposition fighting government forces , but also have seized some government territory .

Al-Assad 's military recently launched its own air strikes on ISIS positions , amounting to what Hof described as a dispute between crime gangs over money -- in this case , from oil fields occupied by ISIS .

Syria ready to cooperate with UN to fight terror

4 -RRB- Will ISIS attack the West ?

To some in the United States , especially critics of Obama , an ISIS attack on U.S. interests and even the homeland is a question of when , not if .

`` ISIS is a very powerful local organization , and probably a reasonably powerful regional terrorist organization , '' former CIA chief Michael Hayden told CNN on Sunday . `` But it 's one that has global ambitions -- and it has the tools . ''

There 's no clear consensus inside the intelligence community as to whether ISIS , which calls itself the Islamic State , is currently capable of striking the West .

`` It 's expressed the intent , '' Hayden said . `` There 's no more powerful way to express their street credentials among the jihadist community than a successful attack against the West . ''

Graham , a consistent advocate for increased U.S. military might , told CNN on Sunday that `` it 's about time now to assume the worst about these guys , rather than to be underestimating them . ''

ISIS threat to the West

5 -RRB- Can the ISIS money flow be stopped ?

Bank robbery , kidnapping , smuggling , selling oil on the black market -- ISIS gets money to fund and expand its organization in all kinds of ways .

Officials say the group can get about $ 3 million a day by selling discounted oil from fields it has seized in Iraq . It also has grabbed millions robbing banks including an Iraqi central bank in Mosul .

Western allies can reduce the group 's income by refusing to pay ransom for abducted citizens and pressuring regional governments to crack down on wealthy citizens sending money to it .

The United States is working with governments in the region , including Kuwait , Qatar and Saudi Arabia , to stop such private donations , State Department spokeswoman Marie Harf said last week .

ISIS oil money

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White House : President Obama has not decided on air strikes in Syria

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Possible options include air strikes on ISIS targets in Syria

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Some consider the group a direct threat to U.S. security

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Obama spent three years avoiding a U.S. military role in Syria